Hi! First off, thank you so much for any help. I am slowly learning electronics and arduinos etc... maybe one day I will be smart enough to help people on here.

I am attempting to build the audio detection circuit found here: http://www.picaxe.com/docs/picaxe_sound.pdf

I arranged it all on a breadboard and I thought I did everything perfect...I am powering the circuit by the 5v from the arduino.The output (0-3v) is connected to an led. presumably the led should turn on when the circuit detects sound.

It does not turn on at all no matter what sound is made. I have tried changing the sensitivity of the two potentiometers. I have also hooked up the output to a multimeter.it reads 0.52v no matter what sound is made or setting of the potentiometers.

Here is a high quality picture of the set up. Since some of the pins under the transistors and capacitors cannot be seen, I drew them in orange: http://i50.tinypic.com/r877r6.jpg

here are a few more pictures at different angles: http://i45.tinypic.com/33dcs1z.jpghttp://i48.tinypic.com/18omdv.jpghttp://i46.tinypic.com/28vrvgn.jpg

1) power it up for the first time through a 100ohm resistor, and measure the voltage over that resistor: this assures you if there is short.2) you need to make sure that the dc working points are correct. Measure voltage on Q1's b / c, Q2's b/e/c, Q3's b/e. and compare them to what you expect. For example, Q1's b should be about 0.7v, Q2's b should float with RV2, etc.3) if you have a scope, it would be helpful but get the dc working points and report back.

1) power it up for the first time through a 100ohm resistor, and measure the voltage over that resistor: this assures you if there is short.2) you need to make sure that the dc working points are correct. Measure voltage on Q1's b / c, Q2's b/e/c, Q3's b/e. and compare them to what you expect. For example, Q1's b should be about 0.7v, Q2's b should float with RV2, etc.3) if you have a scope, it would be helpful but get the dc working points and report back.

ok,

1) I measured the voltage over a 100r resistor in place of the led. It was 0v. I asume this is what you mean telling me there is a short.

2) the voltage I was talking about was the respective points vs. ground.

1) i meant from the output (0-3v) to the ground.

2) oh ok, sorry.

q1: b = 0.63v c = 0.86v q2: b = 4.5-6.5v (depending on sound) e = 5v c = 0 - 3.5v (depending on sound) (the led lights up to sound from this pin to ground, but it doesnt have the slow decay which i am assuming is what the next transistor is for)

OP, after you learn how transistors work, the next step is discovering that opAmp circuits are a much better way to go, in general requiring far fewer components, and producing much better results with a lot less effort,